Colonna is the 3rd rione of Rome, Italy, identified by the initials R. III and located at the city's historic center in Municipio I.

It takes its name from the Column of Marcus Aurelius in the Piazza Colonna, the rione's main square.

[3] In ancient Rome, in the hilly part the richest patricians had their sumptuous domus, while the flat region used to belong to the Campus Martius and was studded with monuments: in addition to the Column of Marcus Aurelius, from which the rione takes its name, also the Temple of Hadrian and the Solarium Augusti were located in the area.

The relevance of Colonna increased further in 1696, after the Palazzo Montecitorio was chosen as the headquarter of the pontifical police and as the seat of the papal courthouse and of the customs house.

Following the unification of Italy and the proclamation of Rome as the capital of the new State, the northwestern part of the rione – hilly and packed with villas and parks – experienced a real "construction fever" as a huge number of new buildings were constructed to satisfy the demands related to the new role of the city.